Messages in this thread | | | Date | Mon, 28 Apr 2008 22:35:35 +0300 | From | Pekka Paalanen <> | Subject | Re: ftrace and debugfs weird interaction |
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> * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote: > > > Hi, > > > > When trying to figure out what was going on with the sched tracer > > "tracing_enabled" file (sched-devel.git tree), I fell on this strange > > behavior : > > > > echo 1>tracing_enabled seems _not_ to send 1 to the tracing_ctrl_write
Wait a minute, are you literally running the command: echo 1>tracing_enabled
If you are, you just echoed only a newline and directed stdout, stream 1, to the file. No? :-)
Could you try with a space: echo 1 > tracing_enabled
> > callback. However, sending garbage, e.g. echo s> tracing_enabled, > > correctly sends the 's' character down the chain. echo 0>tracing_enabled > > sometimes results in the callback not even being called.
Stream 0 is stdin, so... not sure what this would do. Probably nothing, just like you experienced.
Thanks.
-- Pekka Paalanen http://www.iki.fi/pq/
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